NEO4EMF, a Neo4j-based model repository and persistence framework allowing on-demand loading, storage, and unloading of large-scale EMF models. Check us at : https://neo4emf.com Fork us at : https://github.com/neo4emf/Neo4EMF

1. Neo4EMF :
Big Models made possible
Amine BENELALLAM
AtlanMod Research Team
EclipseCon Europe 2013,
Ludwigsburgh, Germany
October 31
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2. Context
Model Management
Model Transformation
Model Versionning
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3. Challenges + solutions
Lazy loading
On demand
loading
Save if dirty
Effective Backend
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4. Database Market
Relational DBs
NoSQL DBs
Column
Document
Key/value
Graph
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5. Graphs & MDD
Natural
Representation
Models as attributed
directed graphs
Graphs
Model
Management
Tech
High performance
Advanced graph
traversal algorithms
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6. Towards Graph DBs to Persist Models
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7. Neo4J
Short presentation
Basic concepts
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8. Neo4j : Short Introduction
Neo4j project started in 2007 in Sweden
First Version (1.0) was released in 2010
More than 10 Versions (active Community)
Current Version 2.0.0-M06 (MileStone)
Labelled nodes
Constrained DB
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9. They trust Neo4j
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10. Neo4j Graph DB concepts
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11. Neo4j Graph DB concepts
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12. Neo4j Graph DB concepts
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13. Neo4j Graph DB concepts
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14. Neo4EMF
Integration
Framework
Process
Data-Representation
What’s new in Neo4EMF
Changelog
Partitioning
Java Ecore codegen
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15. Neo4EMF = EMF+Neo4J_embedded
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16. Framework
Neo4emfUtils
Neo4j
NeoJava codeGen
ChangeLog
Neo4EMF
Eclipse Modeling Framework
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17. Process
Edit/ create Data
Check changes
Notify get / set
Retrieve data
Neo4j Resource
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18. Data Representation
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19. Data Representation
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20. Neo4EMF-Object
A Neo4EMF-Object is simply a :
MinimalEObjectImpl
Additional metadata (ID)
Notifies changes and access
Stores an adapter to capture
notifications and store them in the
changelog
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21. Save : ChangeLog
Lightweight entry set that casts and records
changes notifications
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22. Load : Partitioning
Two kinds of partitions
Flat partitions (to gather elements of the same type)
Tailed partitions (to hold references to other
objects)
Partitions might be flexible
Static/Dynamic Partitioning
Full-Load
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23. Unload : Access History
The Unloader uses the data access
history recorder to unload partitions
Unloading strategies :
LIFO, FIFO
Least recently used
Least frequenty used
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24. NeoJava Codegen
Adapted codegen templates for :
Refined on-demand loading
Data access notification
Costimized AdapterFactory to cast
notifications and store them in the
changelog
Separated objects and data
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25. DemonstrationScenario
Generate
Query
Java.ecore
(it can be any other
plugin)
org.eclipse.emf.ecore
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26. Still more to come
Concurrent Access
Distributed models
Synchronized unloading
More Ecore utilities
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27. Questions
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28. Don’t forget to
Check us out :
www.neo4emf.com
Contact us :
neo4emf@gmail.co
m
Fork us at :
https://github.com/
neo4emf/Neo4EMF
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